Insulinde / Creative CommonsMassachusetts has restricted stores from selling more than $5,000 worth of lottery tickets per day after a couple cracked the secret to winning a game called Cash WinFall. They spent $614,000 over three days and won millions.

Some lottery games aren't entirely about luck as one elderly couple cracked the secret to winning a lesser-known game called Cash WinFall.

Michigan couple Marjorie and Gerald Selbee, both in their 70s, traveled to Massachusetts where they each bought $307,000 worth of the game's $2 tickets over three days in July. They won millions with virtually no risk of losing.

According to Fox News, the trick is timing. Cash WinFall awards the top prize money to anyone who matches all six numbers -- which has only happened once in seven years -- but the jackpot has a limit of $2.5 million. If no one wins during the week that the limit is reached, the prize money is redistributed to those who match three, four or five numbers correctly. Crafty players like the Selbees buy tickets during that last week for a greater chance of winning because they don't need to match all six numbers to win.

Mark Kon, a math and statistics professor at Boston University, told The Boston Globe that gamblers who buy $100,000 worth of tickets during the "rolldown" week have a 74 percent chance of winning. A couple like the Selbees, who spent more than six times that, were pretty much guaranteed to cover their investment -- and profit hundreds of thousands of dollars.

"Cash WinFall isn't being played as a game of chance. Some smart people have figured out how to get rich while everyone else funds their winnings," Mohan Srivastava, an MIT-educated statistician, told The Boston Globe.

Two lottery agents where the couple bought tickets from, Billy's Beer & Wine and Jerry's Place both of Franklin County, Mass., had their licenses suspended Monday over accusations that they broke the rules. MassLive reports the Selbees run a corporation called GS Investment Strategies, LLC and the owners of those two agents, Paul Mardas and Jerry Dagrosa, are members of the corporation.

However, the Selbees' scheme was not against the game's rules or in violation of the law.

Nevertheless, state treasurer Steven Grossman issued a new restriction Tuesday to stores to level the playing field in the Cash WinFall lottery game. Under the new rules, no store will be allowed to sell more than $5,000 worth of tickets in a single day.

"We want to do everything we can to make sure the integrity of the lottery is not questioned in any way, shape, or form," Grossman told The Boston Globe.

Still, despite the previous advantage to strategic players like the Selbees, the game made money. Paul Sternburg, the lottery's executive director says Cash WinFall has earned $11.8 million in profits so far this year.